Just keeping an eye on my local properties week by week, I've concluded the listings on spghotescapes.com are not a reliable guide to what is actually available.

This week, for example, Hot Escapes rates are available at both the Sheraton Heathrow and Sheraton Skyline. Yesterday, neither were listed; today it's just the Skyline.

Best to look on the 'Compare rates' tab on the main spg.com booking engine instead.